1. Field of the Invention
The present invention is broadly concerned with improvements in elongated, multiple-station, in-line product handling equipment of the type used to handle and insert supplements into newspapers or similar products in order to significantly increase the operating speed and reliability of such machines. More particularly, the invention pertains to such equipment wherein an improved, high-speed inserter is provided having a feeder unit for individual feeding of newspaper or like products from a stack thereof together with a receiver unit for receipt of the individually fed products and rapid conveying thereof along the length of the machine. The feeder unit includes a pivotal sucker bar operable for initially gripping the leading end of the lowermost product of a stack and pivoting the end downwardly without any substantial translation of the gripped product; a lightweight translatable and rotatable nip roller then engages the downwardly pivoted product end and, in conjunction with a feeder belt, delivers the product from the stack. The receiving unit has a rotatable feeder wheel equipped with a resilient periphery which engages the fed product and moves it along the length of the machine; the operation of the wheel is correlated with that of a pusher chain unit so that a pusher pin engages the trailing edge of the product substantially simultaneously with the wheel so as to rapidly and positively move the product from the receiver unit. An improved pusher chain assembly is also provided which is made up of a whole number of interconnected chain sections each having a plurality of pin mounts secured thereto which are strategically placed so that the chain assembly can be rapidly modified for handling products of different lengths.
2. Description of the Prior Art
Newspaper sections and advertising tabloids, generally consist of a plurality of flat, identically-sized sheets of paper, wherein the sheets are folded within the next contiguous sheet such that a common centerfold is produced. However, often additional pages, flyers or other materials must be inserted within the section subsequent to the original assembly of the section. In some cases, not all of the sheets intended to be placed within the section are printed at the same time. In other cases, advertising flyers and smaller inserts are printed at a different location and must be placed within the section as soon as the latter is printed. In the past, these inserts have typically been stuffed into a newspaper section by hand. However, this operation is troublesome, labor intensive and time-consuming, causing the price of the final product to increase accordingly.
In recent years, a number of multiple station, in-line machines have been developed for the mechanized handling and inserting of supplements into newspapers and like products. For example, U.S. Pat. No. 4,526,356 discloses a specific insert mechanism useful in this context. Additionally, U.S. Pat. No. 5,125,637 discloses a feeder arrangement for such machines.
While machines of this type represent a decided advancement in the art, there is still a need for improved performance, particularly in the areas of throughput (i.e., number of products handled per hour), reliability and makeready times. For example, existing machines are sometimes plagued by the phenomenon known as "bagging." That is, typical feeders are provided with a sucker bar unit which is oriented to initially grip the lowermost edge of the bottom product of a stack and pivot this edge downwardly to a location where it can be engaged by a nip roller for feeding thereof. However, during this initial pivoting operation there is a tendency to also pull and translate the bottom product relative to the stack. This in turn causes the next adjacent product to buckle or "bag." If this occurs, the next time the sucker bar unit moves upwardly to engage the product, it cannot effectively grip it owing to the presence of the bagged portion. In severe cases, this condition will cause the sucker bar unit to grip the next adjacent product, rather than the bottom most product of the stack, and pull both of them downwardly towards the nip roller. This creates a very significant misfeed or jam, requiring operator intervention and consequent processing slowdown.
Conventional receiving units also have presented problems, principally because of the inability to quickly and cleanly receive the fed products and move them in a transverse direction relative to the feeding direction. Specifically, the feeder unit in such machines delivers the products along a first path of travel to the receiving unit, whereupon the latter must reliably initiate movement of the product in a direction transverse to the first path of travel, at high speeds.
Finally, changeover and makeready time with prior machines has been significant, principally owing to the need to reconfigure the pusher chain assemblies thereof. In particular, these machines have an elongated, continuous chain which supports a plurality of spaced apart pusher pins which are adapted to engage the trailing edges of received products in order to move them along the lengths of the machines. When it is necessary to change over a given machine to handle differently sized products, it can be a time-consuming process to reset the pusher pins along the length of the chain for most efficient handling. Similarly, the makeready for the remaining components of the machine can also be a lengthy process.